Self-adjusting orchard ladder



May 5, F. F. NELSON SELF-ADJUSTING ORCHARD LADDER 3 Sheets-Sheet 1 FiledFeb. 21, 1958 1/ INVENTOR. "Fzeoemcu F. NELSON lxr-rozu EYS;

May 5, 1959 F. F. NELSON 2,885,133

SELF-ADJUSTING ORCHARD LADDER Filed Feb. 21, 1958 3 Sheets-Sheet 2INVENTOR. TQEDEmcK'F. Mason ATToEjdEYs May 5, 1959 F. F. NELSON2,885,133

SELF-ADJUSTING ORCHARD LADDER Filed Feb. 21, 1958 s Sheets-Sheet 5 k 7INVENTOR.

nznsmcz F. NELsoM AT TO QM EYS SELF-ADJUSTIN G ORCHARD LADDER FrederickF. Neison, Spokane, Wash, assignor of one-half to Robert D. Grant,Tonasket, Wash.

Application February'21, 1958, Serial No. 716,735

7 Claims. (Cl. 22863) This invention relates to ladders, and moreparticularly to an orchard ladder provided with means for adjusting thesupporting legs thereof automatically to irregularities of thesupporting terrain.

A main object of the invention is to provide a novel and improved ladderespecially useful for harvesting fruit and similar activities, theladder being simple in construction, being easy to set up for use, andbeing provided with means for automatically adjusting the ladder toirregularities in the supporting terrain, whereby the ladder will besafely held in an upright position when used on a slope or on groundwhich is irregular or rough.

A further object of the invention is to provide an improved orchardladder which is inexpensive to manufacture, which is durable inconstruction, which may be rapidly and easily set up for use, and whichis self-adjusting so that it will safely support the person using sameregardless of irregularity of the ground on which it is placed.

Further objects and advantages of the invention will become apparentfrom the following description and claims, and from the accompanyingdrawings, wherein:

Figure 1 is a front elevational view of an improved orchard ladderaccording to the present invention, shown supported on a slope.

Figure 2 is a side elevational view of the ladder of Figure 1.

Figure 3 is .a horizontal cross-sectional view taken on the line 3-3 ofFigure 2.

Figure 4 is an enlarged cross-sectional view taken substantially on theline 44 oflFigure 2.

Figure 5 is an enlarged perspective view showing a lower side portion ofthe ladder of Figure 4 with the elements thereof in various positions. 7

Figure 6 is an enlarged cross-sectional detail view taken on the line6-6 of Figure4.

Figure 7 is a cross-sectional view taken on the line 7-7 of Figure 6.

Figure 8 is a cross-sectional view taken on the line 88 of Figure 7.

Figure 9 is an enlarged cross-sectional detail view taken 'on the line9-9 of'Figure 3.

Figure 10 is'a cross-sectional view taken on the line 1ii1tl of Figure9.

Referring to the drawings, 11 generally designates an orchard ladderaccording to the present invention, shown set up for use on a slope 12.The ladder 11 comprises a supporting frame 13 having the upwardlyconverging side members 14, 14 which are connected by the rungs 15 andwhich are rigidly connected at their top ends by the platform member 16.The bottom ends of the side bars 14-, 1d are rigidly connected by across bar 17 and project outwardly beyond the bottom ends of the sidebars 14, 14.

Designated respectively at 18, 18 are inclined brace bars which arerigidly connected at their lower portions 2,885,133 Patented May 5, 1959to their respective opposite ends of the cross bar 17, as by therespective bottom corner angle brackets 19, 19. The top ends of thebrace bars 18, 18 are tapered, as shown at 20, and are rigidly securedto the outside surfaces of the side bars 14, 14 in any suitable manner,for example, by the tie rod 21 of one of the rungs 15, the ends of saidtie rod extending through apertures in the tapered end portions of thebrace bars 18, 18 and clamping said end portions to the side bars 14, 14'by the fastening nuts 22 provided on the respective opposite ends ofthe 'tie rod 21.

As shown in Figure 4, the lower end portions of the brace bars 18, 18project below the cross bar 17.

Designated respectively at 23, 23 are supporting leg members which areslidably connected to the bracebars 18, 18 at the outer sides thereof,for example, by respective pairs of guide sleeve members 24, 24 and 25,25. The guide sleeve members 24 are secured to the lower ends of thebrace bars 18, 18 and slidably receive the legs 23, whereas the guidesleeves 25 are secured to the top ends of the legs 23 and slidablyreceived the brace bars 18. This is clearly shown in Figure 4.

The brackets 19 are formed with the transversely extending, hollow guideblock elements 26 which are spaced from the corners defined between thecross bar 17 and the brace bars 18, 18 to define guide passageways, asshown in Figure 4. Designated at 27 is a first cable rnem-ber whose endsare fastened to the lower end portions of the slidableleg members 23, 23and which passes upwardly through the guide sleeves 24, through guideopenings 28 in the lower portions of the brace bars 18, 18 and throughthe guide passageways defined above the guide block members 26, 26. Asshown in Figure 5, the slidable leg members 23 are formed on theirinside surfaces with vertical guide grooves 29 in which the sideportions of the cable 27 are received.

The intermediate portion of cable 27 passes between generally horizontalupper and lower clamping plates 30 and 31, as shown in Figure 7, andextending over the end portions of the clamping plates are respectiveyoke members 32, 32, said yoke members being pivotally connected attheir intermediate portions to the respective ends of the lower clampingplate 31 by transverse hinge pins 33, 33 connecting the intermediateportions of the side arms of the yoke members and passing throughrespective transverse hinge sleeves 34, 34 formed on the ends of thelower clamping plate 31. The upper clamping plate 30 is turned upwardlyat itsrespective'ends, as shown at 35, 35, the bight portions 36, 36 ofthe respective yoke members 32, 32 being received inwardly adjacentrespective upturned end flanges 35, 35 on the upper clamping plate 30.

As will be readily apparent from Figure 7, the bight portions 36, 36 ofthe yoke members 32, 32 are of substantial width, whereby said bightportions exert a downward clamping force on the upper clamping plate 30when the lower portions of the bight members 32, 32 are rotatedoutwardly.

The lower ends of the respective yoke members 32, 32 are connected bytransverse pins 37, 37, and a coil spring 38 is connected between thepins 37, 37, biasing the lower portions of the yoke members 32, 32towards each other, whereby to normally relieve the clamping force onthe upper clamping plate 30.

Designated respectively at 39, 39 are additional cable members connectedrespectively to the top portions of the slidable leg members 23, 23 andextending downwardly through the grooves 29 and passages 28 around thelower end surfaces of the transverse guide blocks 26. The inner ends ofthe cables 39 are connected respectively to the transverse pin member 37of the yoke members 32, whereby a load placed on the supporting frame 13is transmitted tothe cable members 39,39 through the brace bars 18, 18,developing tension in the cable members 39, 39 and thus tending torotate the lower portions of the yoke members 32, 32 outwardly, wherebytocause the bight portions 36, 36 of said yoke members to exert downwardclamping force on the upper clamping plate 34.

Theclamping plates 30, 31 are formed with respective opposinglongitudinal channels 40, 41in which the intermediate portion of cable27 is received, and is clamped when the above described clamping forceis applied to the upper clamping plate 30. Designated at 42 is arearwardly extending supporting leg which is hingedly connectedat 43 tothe intermediate portion of the cross bar 11, saidsupporting leg beingprovided at its outer end with a ground-engaging skid bar 44, as isclearly shown in Figure 2. The supporting leg 42 is constrained torotatearound the transverse axisof thehingeconnection by respectiveinclined guide struts 45, 45 connecting the intermediate portions of theleg 42 to respective pivot brackets 46, 46 secured on the opposite endportionsofthecrossbarfl.

The :rearwardly extending leg 42 is preferably T-shaped in cross sectionand the end portions of the link bars 45, 45 are pivotally connected toopposite sides of the depending flange 48 of leg 42 by a commontransverse hinge rivet Slidably mounted on the head portion of the1'-shaped leg 42 is a shoe member 49, said shoe member being providedwith opposing pairs of channeled side flanges 50, 59 which slidably,engage around the respective opposite edges of the head portion 51 ofleg member 42. The inportion of the shoe member 49 is formed withrespective upstanding lugs 52, 52 projecting upwardly from the oppositeside margins of shoe member 49 between the respective channeled flangemembers 50, 50 at said side portions, and each lug 52 is connected by alink bar 53 to a respective side bar 14 of the supporting framel3.Thelinkbars53areconnectedtotheside bars 14 at the same height, wherebysaid link bars 53 define a linkage connection with the shoe member 49,allowingsaid shoe member to be adjusted along the head 51 of theT-shaped leg member 42, and at times allowleg member 42 to be foldedupwardly to a position closely adjacent to the plane of the supportingframe 13. Thus, the leg 42 may be at times folded to a position closelyadjacent to the frame 13, whereby the bulk of the ladder device isreduced to a minimum, facilitating the transportation and storage ofsaid ladder A common transverse pivot pin 55 extends through the lugs52,52 and throughthe outer ends of the link bar 53. Rigidly connected tothe intermediate portion of the pin 55, between the upstanding lugs 52,52, is a longitudlnsily extending dog member 56 which overlies the rearportion of the shoe member 49, as shown in Figure 9, and which isprovided at itsouter ends with the depending lockinglingers 57, 57 whichare engageable in opposing pairs of notches 58, 58 formed in the headmember 51 of leg 42 at spaced locations therealong, whereby to lock theshoe member 49 adjacent said locations.

Secured to the top surface of the dog 56 at its intermediateportion is abracket member 59 formed at one end with an upstanding abutment 60 andhaving a fastening ring 61 secured to its opposite end. The shoe member49 is formed at its forward end with an upstand' ing transverse flange62, and a leaf spring 63 is secured at its intermediate portion to anupstanding stud member 64 provided on the shoe member 49, as shown inFigure9, whereby the leaf spring is held in engagement with the flange62 and abutment member 60, exerting a downward biasing force on thelocking dog 56.

A release cable 66 extends through respective eye members 67, 67 securedto the upper end portions of the link rods 53, 53 and has its endfastened to the upwardly projecting eye member 61, whereby a pull on thetransversely extending portion of the release cable 66 elevates thelocking dog 55 against the biasing force of the leaf spring 63, causingthe lugs 57, 57 to disengage from the notches 58, 58, and allowing theshoe member 49 to be moved along the leg 42. This allows the leg 42 tobe adjusted to a desired position relative to the supporting frame 13,for example, to the supporting position thereof shown in Figure 2,cooperating with the adjustable leg members 23, 23 to support the frame13 in an upstanding operative position.

As will be readily apparent, when the device is set up on slopingground, for example, on the slope 12, the legs 23, 23 automaticallyadjust themselves relative to their associated brace bars 18, 18, sothat the frame 13 will, be arranged in its correct upstanding position.Similarly, the rearwardly extending leg member 42 is adjusted to thedesired position thereof to support the frame l3 in its correctupstanding position. When the user mounts the supporting frame 13, theweight thus placed on the frame drvelops tension in the cable members39, 39, causingthe lower portions of the yoke members 32, 32, to berotated outwardly, as above described, thus causing the bight portions36, 36 of said yoke members to exert downward clamping force on theupper clamping plate 30, which locks the cable 27 and thus secures theslldable leg members 23, 23 in their adjusted positions, whereby theframe 13 is rigidly supported in its correct adjusted upstandingposition as long as the user remains thereon.

While a specific embodiment of an improved orchard ladder has beendisclosed in the foregoing description, it will be understood thatvarious modifications within the spirit of the invention may occur tothose skilled in the art. Therefore, it is intended that no limitationsbe placed on the invention except as defined by the scope of theappended claims.

What is claimed is:

1. In an orchard ladder, a supporting frame, respec' tive leg membersslidably connected to opposite sides of said supporting frame,respective cable guide members at the lower portions of said oppositesides, a first cable member connecting the lower end portions of saidleg members and extending slidably through said cable guide members,respective additional cable members connected at their outer ends to theupper end portions of said leg members and extending slidably throughsaid cable guide members, and means connecting the inner ends of saidadditionalcable members.

2. In an orchard ladder, a supporting frame, respective leg membersslidably connected to opposite sides of said supporting frame,respective cableguide members at the lower portions of said oppositesides, a first cable member connecting the iowerend portions of said legmembers'and extending slidably through 'said cable guide members,respective horizontal clamping plates disposed above and below theintermediate portion of said first cable member, respective yoke membersdisposed around said clamping plates and pivotally connected to thelower clamping plates with their bight portions overlying the upperclamping plates, respective additional cable members connected at theirouter ends to the upper end portions of said leg members and extendingslidably through said cable guide members, and means connecting theinner ends of said additional cable members to the respective yokemembers below the lower clamping plate, whereby outward force on saidadditional cable members rotates the bight portions of said yoke memberstoward said upper clamping plate to exert clamping force on the upperclamping plate.

3. In an orchard ladder, a supporting frame, respective leg membersslidably connected to opposite sides of said supporting frame,respective cable guide members at the lower portions of said oppositesides, a first cable member connecting the lower end portions of saidleg members and extending slidably through said cable guide members,respective horizontal clamping plates disposed above and below theintermediate portion of said first cable member, respective yoke membersdisposed around said clamping plates and pivotally connected to thelower clamping plate with their bight portions overlying the upperclamping plate, spring means connecting the portions of said yokemembers below the lower clamping plate and biasing the bight portions ofsaid yoke members away from said upper clamping plate, respectiveadditional cable members connected at their outer ends to the upper endportions of said leg members and extending slidably through said cableguide members, and means connecting the inner ends of said additionalcable members to the respective yoke members below the lower clampingplate, whereby outward force on said additional cable members rotatesthe bight portions of said yoke members toward said upper clamping plateto exert clamping force on the upper clamping plate.

4. In an orchard ladder, a supporting frame, respective leg membersslidably connected to opposite sides of said supporting frame,respective cable guide members at the lower portions of said oppositesides, a first cable member connecting the lower end portions of saidleg members and extending slidably through said cable guide members,respective horizontal clamping plates disposed above and below theintermediate portion of said first cable member, respective yoke membersdisposed around said clamping plates and pivotally connected to thelower clamping plate with their bight portions overlying the upperclamping plate, a coiled spring connecting the portions of said yokemembers below the lower clamping plate and biasing said bight portionsof the yoke members away from said upper clamping plate, respectiveadditional cable members connected at their outer ends to the upper endportions of said leg members and extending slidably through said cableguide members, and means connecting the inner ends of said additionalcable members to the respective yoke members below the lower clampingplate, whereby outward force on said additional cable members rotatesthe bight portions of said yoke members toward said upper clamping plateto exert clamping force on the upper clamping plate.

5. In an orchard ladder, a supporting frame, respective leg membersslidably connected to opposite sides of said supporting frame,respective cable guide members at the lower portions of said oppositesides, a first cable member connecting the lower end portions of saidleg members and extending slidably through said cable guide members,respective horizontal clamping plates disposed above and below theintermediate portion of said first cable member, respective yoke membersdisposed around said clamping plates and pivotally connected to thelower clamping plate with their bight portions overlying the upperclamping plate, said yoke members having portions depending below saidlower clamping plate, spring means connecting said depending portions ofsaid yoke members and biasing the bight portions of said yoke membersaway from said upper clamping plate, respective additional cable membersconnected at their outer ends to the upper end portions of said legmembers and extending slidably through said cable guide members, andmeans connecting the inner ends of said additional cable members to saiddepending portion of the respective yoke members below the lowerclamping plate, whereby outward force on said additional cable membersrotates the bight portions of said yoke members toward said upperclamping plate to exert clamping force on the upper clamping plate.

6. In a ladder, a supporting frame, a rearwardly extending supportmember connected to the frame, respective cable guide members at thelower portions of said opposite sides, a first cable member connectingthe lower end portions of said leg members and extending slidablythrough said cable guide members, respective additional cable membersconnected at their outer ends to the upper end portions of said legmembers and extending slidably through said cable guide members, meansconnecting the inner ends of said additional cable members, and a clampreleasably engaging said first cable member, said connecting meansincluding clamp closing members connected to the clamp and operable byoutward pull on said additional cable members to close the clamp on saidfirst cable member.

7. In a ladder, a supporting frame, respective leg members slidablyconnected to opposite sides of said supporting frame, respective cableguide members at the lower portions of said opposite sides, a firstcable member conmeeting the lower end portions of said leg members andextending slidably through said cable guide members, respectivehorizontal clamping plates disposed above and below the intermediateportion of said first cable member, respective yoke members disposedaround said clamping plates and pivotally connected to the lowerclamping plates with their bight portions overlying the upper clampingplates, respective additional cable members connected at their outerends to the upper end portions of said leg members and extendingslidably through said cable guide members, means connecting the innerends of said additional cable members to the respective yoke membersbelow the lower clamping plate, whereby outward force on said additionalcable members rotates the bight portions of said yoke members towardsaid upper clamping plate to exert clamping force on the upper clampingplate, and a rearwardly extending support member hingedly connected tosaid supporting frame.

References Cited in the file of this patent UNITED STATES PATENTS1,118,199 Hawk Nov. 24, 1914 2,330,825 Hoit Oct. 5, 1943 2,835,427Balcar May 20, 1958 UNITED STATES PATENT OFFICE CERTIFICATE OFCORRECTION Patent Nos 2,885,133 May 5, 1959 Frederick F. Nelson It ishereby certified that error appears in the -printed specification of theabove numbered patent requiring correction and that the said LettersPatent should read as corrected below.

Column 6, line 14, after "i'reme,' insert respective leg membersslidably connected to opposite sides of said supporting frame,

Signed and sealed this 17th day of November 1959.

Attest:

ROBERT C. WATSON KARL H, AXLINE Attesting Ofiicer Commissioner ofPatents

